A phased-array antenna may include a plurality of radiating antenna elements configured to simultaneously emit signals in accordance with a beamforming scheme.
For example, the phased array antenna may be controlled to form a beam directed in a particular direction, or to receive a beam from a particular direction, by shifting phases of the signals emitted by the plurality of antenna elements. The phases of the signals emitted by the antenna elements may be shifted, for example, to provide a constructive and/or destructive interference configured to steer the beam in the particular direction.
A plurality of phase shifters may be associated with the plurality of antenna elements to control the phase shifts applied by the plurality of antenna elements. For example, each phase shifter may shift the phase state of a respective antenna element.
A set of required phase values to be applied to the antenna elements may be determined, e.g., by a phase estimator, for steering the beam in the particular direction, or for receiving the beam from the particular direction.
The phase shifters may include digital devices or analog devices, which are digitally controlled. Accordingly, the phase shifters may only be able to apply to the antenna elements phase states, which are selected from a predefined set of phase state values.
The number of phase state values may depend, for example, on a bit-size utilized by the phase shifter for representing the phase values. For example, a two-bit phase shifter may only be able to apply four phase state values, e.g., zero degrees (°), 90°, 180° and 270°.
In order to comply with the set of phase state values, the set of required phase values may be quantized, e.g., by assigning a quantized phase value to represent each of the required phase values.
A quantization error may result from the quantization process. The quantization error may affect an accuracy of the beamforming.